CarSpecsHQ

225/45R17 vs 205/50R17

205/50R17 is a safe swap for 225/45R17 by the usual ±3% rule: the diameter differs by +0.39%.

17" rim
225/45R17 24.97" · 205/50R17 25.07" · drawn to scale

Side by side

225/45R17205/50R17Difference
Overall diameter24.97"25.07"+0.10" (+0.39%)
Section width225 mm205 mm-20 mm
Sidewall3.99"4.04"+0.05"
Rim17"17"same
Circumference78.5"78.8"+0.3"
Revs per mile808804-3
Ride height——+0.05"
Speedometer reads 60 mph60.060.2+0.2 mph

Speedometer and odometer

020406080100120 reads 60 · actual 60.2 mph

With 205/50R17 on a car calibrated for 225/45R17, the speedometer reads 59.8 mph when you're really doing 60, and the odometer under-counts by 0.4%.

Speedo showsActual speed
30 mph30.1 mph
45 mph45.2 mph
60 mph60.2 mph
70 mph70.3 mph
80 mph80.3 mph

Other sizes close to 225/45R17

Questions

Can I replace 225/45R17 with 205/50R17?

205/50R17 is a safe swap for 225/45R17 by the usual ±3% rule: the diameter differs by +0.39%.

What's the difference between 225/45R17 and 205/50R17?

205/50R17 is 0.10" taller and 20 mm narrower; the sidewall is +0.05". At an indicated 60 mph you'd actually be doing 60.2 mph.

Will 205/50R17 fit on 225/45R17 wheels?

Both use a 17" rim, so the wheel diameter matches; check the wheel's width range for a 205 mm tire and the fender clearance.